环糊精包合技术对白藜芦醇在化妆品中应用的改善作用

按照饱和水溶液法,以羟丙基-β-环糊精做包合剂制备白藜芦醇包合物的水溶液,通过含量、外观、pH值等指标,考察其在不同条件下的稳定性.通过ABTS和DPPH自由基清除实验、脂质过氧化实验、细胞氧化应激实验综合评价白藜芦醇包合物的抗氧化活性.测试结果表明,白藜芦醇在包合物水溶液中的含量可达1.0％以上,水溶液的稳定性显著提...     

钩藤碱β-环糊精包合的制备及其热稳定性初步研究

采用饱和水溶液法进行包合,利用紫外分光光度法进行物相鉴别以及用烘箱进行热稳定性实验。研究了β-环糊精包合钩藤碱的最佳工艺并对包合物稳定性进行初步研究。结果表明:经紫外分光光度法鉴定,表明钩藤碱-β-环糊精确已形成包合物,其条件是钩藤碱与β-CD比为1∶7,乙醇最佳浓度为80%,包合最佳时间为15 min。热稳定性实验对包合物的稳定进行测定,表明了钩藤碱β-CD包合物的热稳定性明显优于混合物。本试验中当钩藤碱与β-CD形成包合物以后能明显提高稳定性,采用饱和水溶液法制备的钩藤碱β-CD包合物操作简便,成本低,对设备要求不高,且稳定性好,具有一定推广应用价值。     

多重乳化体在化妆品中应用的研究进展

综述了多重乳化体的乳化剂、水相、油相等组成及制备工艺对多重乳化体的稳定性与生成率的影响;介绍了多重乳化体在化妆品中对活性物的包裹、缓释及隔离等的应用;指出制备稳定的多重乳化体的研究方向。     

多元醇与中药提取物组合物在化妆品中的应用

研究了一种含多元醇及几种中草药提取物的化妆品用防腐组合物,通过复配组合,提供一种新颖的化妆品用防腐组合物,结果表明该组合物与绝大多数化妆品原料兼容性很好,具广谱抗菌活性,能有效抑制革兰氏阴性菌、革兰氏阳性菌、酵母菌及霉菌,其抑菌能力不受化妆品中表面活性剂的影响。     

白藜芦醇丙烯酸酯的合成及抗氧化活性研究

以白藜芦醇为先导化合物,合成了白藜芦醇丙烯酸酯,以获得具有更好抗氧化活性的白藜芦醇衍生物。以白藜芦醇和丙烯酰氯为原料,酯化法得到白藜芦醇丙烯酸酯。以维生素C为阳性对照,研究白藜芦醇丙烯酸酯对2,2-联苯-1-苯基肼(DPPH)自由基的清除活性和抗氧化活性。用NMR和HRLC-MS对白藜芦醇丙烯酸酯进行了表征。目标产物白藜芦醇丙烯酸酯收率为30.2%。白藜芦醇丙烯酸酯的抗氧化活性高于白藜芦醇,但低于维生素C。合成得到了白藜芦醇丙烯酸酯,其反应路线简单易行,条件温和,产物抗氧化活性较先导化合物有所提高。     

化妆品、食品工业应用的环糊精包接物的制备

β-环糊精作为包合剂在制药、食品和化妆品等工业中有着广泛的应用，其报导屡见不鲜，然而有关它的包接物制备方法却介绍得很少。为此，本文将在这方面作一些简单描述。β-环糊精是以葡萄糖为单元通过α－1，4键相连接而成的环状化合物，分子结构形似水桶，中央是空的，能包接各种有机物质。它有性质稳定、使用安全、无毒、可食用等优点。为把客体分子活性物包埋在主体分子环湖精内，现在尚无定型的制作工艺。但从巴搜集到的资料来看，目前用于制备环糊精包接物的方法归纳起来大致有这样三种：液相法、半固相法和固相法。现将它们分别介绍如…     

六氢β-酸环糊精包合物抑菌活性及其稳定性研究

以金黄色葡萄球菌和大肠杆菌为供试菌,研究六氢β-酸环糊精包合物抑菌活性及其稳定性。采用滤纸片法测定7种环糊精包合物抑菌活性,二倍稀释法测定六氢β-酸-2,6二甲基-β-CD、六氢β-酸-2-甲基-β-CD和六氢β-酸-羟丙基-β-CD包合物的最低抑菌浓度,并研究了温度、pH、紫外线对前述3种包合物抑菌稳定性的影响。结果表明：7种环糊精包合物均有不同程度的抑菌活性,其中六氢β-酸-2,6二甲基-β-CD、六氢β-酸-2-甲基-β-CD和六氢β-酸-羟丙基-β-CD包合物抑菌效果最好,最低抑菌浓度均为8.0 μg/mL。经酸碱处理后,与未处理组比较,在pH>6的条件下,3种包合物的抑菌活性增强,在pH<6的条件下,其抑菌活性减弱;温度和紫外线对3种包合物抑菌活性无影响。     

光甘草定微胶囊包合物制备

研究以明胶和阿拉伯胶为壁材,采用复凝聚法研究了光甘草定微胶囊的制备工艺,探讨了芯壁质量比、增溶剂使用量、乳液均质时间和搅拌速度的影响,通过正交试验确定最佳工艺条件为芯壁比为2∶1,增溶剂为0.5%,均质时间为10 min,搅拌速度为750 r/min。通过本工艺制备得到的光甘草定微胶囊包裹率可达40%,粒径分布均匀(平均粒径3.91μm),将其喷雾干燥后得到光甘草定微胶囊粉末为淡黄色,无刺激气味,可溶于丙二醇等有机溶剂。包裹后的光甘草定微胶囊,减淡了原有的棕黑颜色和刺鼻气味,可很好地用作化妆品美白添加剂。     

生育酚纳米乳液的制备及性能研究

为提高α-生育酚（α-Toc）的稳定性和活性,利用超分子包合机理制备纳米乳液,得到了一种稳定性好、透皮效果佳、抗氧化性能优异的α-Toc纳米传递载体。考察了聚山梨醇酯（Tween）的种类、羟丙基-β-环糊精（HP-β-CD）的添加量和α-Toc溶液的添加量对纳米乳液粒径的影响,并借助傅里叶红外光谱、透射电子显微镜、纳米粒度分析仪、热重分析仪和Franz扩散池研究了α-Toc纳米乳液的包埋情况和性能评价。结果表明,所制备的α-Toc超分子纳米乳液的粒径小且分布均匀,在0℃和室温条件下具有良好的储藏稳定性。纳米乳液可以显著增强α-Toc的热稳定性,比未经过包裹的α-Toc具有更优异的抗氧化能力,纳米乳液在化妆品配方中可有效促进α-Toc的透皮吸收。     

用于组合活性物透皮共递送的环糊精复合物传质体的制备与表征

以卵磷脂、胆固醇、表面活性剂为壁材制备传质体,通过薄膜水合法分别将苯乙基间苯二酚(PR)与白藜芦醇/羟丙基-β-环糊精(RSV/HP-β-CD)复合物包封在传质体的磷脂双分子层和水性隔室中,获得环糊精复合物传质体(DCTs)。研究了膜软化剂及其添加量、添加方式对DCTs粒径、PDI、Zeta电位、包封率的影响。结果表明,使用0.012 mol/L的T20制得的DCTs粒径较小,为112.43 nm,PDI为0.16,Zeta电位为-34.90 mV,PR与RSV包封率最高,分别为77.07%和60.67%。通过对DCTs体外释放、透皮、细胞毒性及B16-F10细胞内黑色素含量研究,发现DCTs实现了活性物缓释并防止活性物降解,减小了组合活性物透皮递送的渗透性差异,降低了游离活性物的细胞毒性,增强了组合活性物的协同效果,从而减少了B16-F10细胞的黑素生成。     

混合溶剂制备Mg/Al水滑石

在水与有机溶剂组成的混合溶剂中,采用均相沉淀水热法制备了Mg/Al水滑石.研究了有机溶剂种类和添加量对水滑石性能的影响,通过X射线粉末衍射、热重分析、扫描电子显微镜和氮吸附仪表征了水滑石的结晶度、热稳定性、形貌以及比表面积.结果表明:添加少量有机溶剂后可得到形貌规整,结晶度和热稳定性能没有明显变化的水滑石粉体,但少量有机溶剂的添加对水滑石粒径尺寸影响较大,粒径尺寸从2μm减小到1 μm左右.随着有机溶剂添加量的增加,粉体粒径明显减小,比表面积则随之增大.     

Effects of Polyols and Organic Solvents on Thermostability of Lipase

The effects of polyols and organic solvents on the thermostability of lipase were studied. The thermodeactivation process of lipase obeyed a series deactivation model and four kinetic parameters were determined. The rate constant of the first deactivation process was found to be a key one. All the polyols used had a positive effect for stabilization of lipase and the extent of effect increased with polyol concentration and carbon number of polyol. The effect of organic solvents on the thermostability of lipase was investigated by incubating the lipase in the organic solvents before measuring their activities. The behavior of the thermodeactivation depended upon the organic solvents used; increased activity was observed in some solvents. © 1997 SCI     

Preparation and properties of a silver particle-coated and 1-dodecanethiol-modified superhydrophobic melamine sponge for oil/water separation

A Ag particle-coated and 1-dodecanethiol-modified melamine sponge (Ag-DDT-MS) was prepared through surface roughness by coating silver particles and subsequent grafting of a hydrophobic long hydrocarbon chain. Superhydrophobic and 3D porous Ag-DDT-MS was characterized by Fourier transform infrared spectroscopy, scanning electron microscope, energy-dispersive X-ray spectroscopy, and X-ray diffraction. The water contact angle of Ag-DDT-MS reached 159.2°. Ag-DDT-MS exhibited excellent absorption capacity for high viscous oils and organic solvents, ranging from 42.8 to 105.2 g∙g⁻¹. The absorbed oils can be easily collected by the mechanical pressing process, and the oil recovery rate was satisfactory, more than 90% after 20 recycles. Ag-DDT-MS material also demonstrated good stability and excellent compression-recovery ability, keeping 88.6% of the initial height after ten compression-release cycles.     

白藜芦醇诱导Raji细胞死亡的自噬途径

目的探讨白藜芦醇对Burkitt B淋巴瘤Raji细胞的增殖抑制作用及诱导死亡途径。方法用白藜芦醇处理Raji细胞,透射电镜及MDC染色检测细胞死亡;Western blot法检测Caspase-3、细胞色素c及CathepsinD蛋白的表达。结果白藜芦醇可明显抑制Raji细胞增殖,电镜观察细胞内出现了大量的自噬小泡,MDC染色后细胞点块状荧光结构明显增加。Western blot分析显示,白藜芦醇可引起细胞色素c从线粒体释放,但释放量与Jurkat细胞相比明显减少,且不能导致Caspase-3的活化。Cathepsin D活性成分32kD片段随白藜芦醇处理时间的延长而减少。结论白藜芦醇可抑制Raji细胞增殖,并通过Caspase非依赖途径诱导细胞自噬死亡。     

Aqueous/ionic liquid interfacial polymerization for preparing polyaniline nanoparticles

The interfacial polymerization of aniline at aqueous/IL has been conducted. The product was characterized by transmission electron microscope (TEM), X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), UV-vis spectroscopy, thermal gravimetric analysis (GTA), and electrical conductivity measurement. In this route, both solvents used are environmentally benign and polyaniline (PANI) particles with diameters from about 30-80 nm can be fabricated. We believe that this method can be used to synthesize some other useful polymers.     

Combining Soft Chemistry and Spark Plasma Sintering to Produce Highly Dense and Finely Grained Soft Ferrimagnetic Y3Fe5O12 (YIG) Ceramics

We report the synthesis of yttrium iron garnet (YIG) combining soft chemistry route, namely the polyol process, and spark plasma sintering (SPS) technique. The polyol process produced an intermediary amorphous phase containing both iron and yttrium cations in the desired ratio. They were annealed at 400°C in air to decompose the organic content of the reaction (polyol and acetate). To achieve the garnet phase, the polyol‐obtained precursor was subjected to reactive SPS treatment at a temperature of 750°C, far below the typical temperatures (1350°C) used in the classic solid‐state reaction process. In 15 min pure and high‐density Y₃Fe₅O₁₂ ceramic, with about 100 nm sized crystalline grains, was obtained. We report as well the characterization of the initial amorphous phase and the obtained YIG by X‐ray diffraction, scanning electron microscopy, Fourier‐transform infrared spectroscopy, ⁵⁷Fe Mössbauer spectrometry, and magnetization measurements.     

软泡用环保型聚醚多元醇的研发及其应用

为减少聚醚多元醇可挥发物质的含量,满足高端市场的要求,高桥石化开发了用于普通软泡的环保型聚醚多元醇GEP-330A以及高活性聚醚脱气味处理工艺。使用GEP-330A可以大大减少胺类催化剂的用量。采用高活性聚醚脱气味处理工艺,使得高活性聚醚多元醇中可挥发性物质大幅降低。     

Structure–property relationship in epoxy‐silica hybrid nanocomposites: The role of organic solvent in achieving silica domains

The thermo‐mechanical properties of a series of epoxy‐silica hybrid composites prepared through sol–gel process are evaluated in a manner that the effect of organic solvent on the formation of silica domains is highlighted. By means of infrared spectroscopy, small‐angle X‐ray scattering, scanning electron microscope, dynamic mechanical thermal analysis, and thermo‐gravimetric analyzer, the specimens were morphologically studied varying the type of organic solvent. Among polar and nonpolar solvents incorporated by the organic–inorganic hybrid system, a mixture of xylene and ethanol (3:1) was properly comparable with tetrahydrofuran (THF) solvent regarding appearance and thermo‐mechanical characteristics. Enhanced thermal stability and modulus was observed upon increasing solvent content. Also, a proper dispersion of silica domains throughout the epoxy was seen in the case that the xylene/ethanol mixture or THF served as solvent. It is to be emphasized that the assigned mixture is environmentally better than that of THF. J. VINYL ADDIT. TECHNOL., 21:305–313, 2015. © 2014 Society of Plastics Engineers     

Efficient synthesis of graphene sheets using pyrrole as a reducing agent

The efficient synthesis of graphene sheets using pyrrole as a reducing agent was explored. The obtained graphene sheets were dispersible in organic solvents such as ethanol, isopropanol, N,N-dimethylformamide, N-methylpyrrolidone, dimethylsulfoxide, tetrahydrofuran, and acetone. During this reduction reaction, pyrrole was oxidized, forming oxidation product of pyrrole and adsorbed on the graphene sheets surface by π–π interaction. The oxidation product of pyrrole acted as a capping agent for graphene sheets by preventing re-stacking and formed organically dispersible graphene. The formation of graphene and its crystalline nature was indicated by the transmission electron microscopy and the atomic force microscopy analysis. Raman, X-ray photoelectron spectroscopy and X-ray diffraction provided the evidence for graphene formation from graphene oxide precursor. Furthermore, the reduced oxygen content and N 1s peak observed by the X-ray photoelectron spectroscopy analysis of graphene sheets confirmed the reduction reaction and presence of adsorbed oxidation product on the surface of graphene sheets. The resulting graphene sheets were readily dispersible in solvents and easily to process.     

水可分散型聚酯多元醇反应动力学研究

用质量分数为5％的间苯二甲酸二甲酯．5-磺酸钠与1，4-丁二醇进行酯交换，其交换后的二醇以及1，4-丁二醇的混合物再和己二酸缩舍得水可分散的聚酯多元醇，用红外光谱仪(IR)和核磁共振仪(^1H NMR)对产物结构进行了表征，并对酯化反应动力学进行了研究。在无外加酸的催化下，考察了反应温度、反应时间等与酯化反应速率的关系，对反应的机理进行了推导，并对试验结果进行了解释。研究结果表明，上述体系在无外加酸存在下，不同于一般的聚酯缩舍聚合，其过程符会二缀半反应动力荤．